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Lifetime of Objects Allocated with new

Objects allocated with the new operator are not destroyed when the scope in which they are defined is exited. Because the new operator returns a pointer to the objects it allocates, the program must define a pointer with suitable scope to access those objects. For example:

// expre_Lifetime_of_Objects_Allocated_with_new.cpp
// C2541 expected
int main()
{
    // Use new operator to allocate an array of 20 characters.
    char *AnArray = new char[20];

    for( int i = 0; i < 20; ++i )
    {
        // On the first iteration of the loop, allocate
        //  another array of 20 characters.
        if( i == 0 )
        {
            char *AnotherArray = new char[20];
        }
    }

    delete [] AnotherArray; // Error: pointer out of scope.
    delete [] AnArray;      // OK: pointer still in scope.
}

Once the pointer AnotherArray goes out of scope in the example, the object can no longer be deleted.

See Also

Reference

new Operator (C++)